<template>
    <div>
        <!-- 面包屑导航 -->
        <el-breadcrumb separator-class="el-icon-arrow-right">
            <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
            <el-breadcrumb-item>商品管理</el-breadcrumb-item>
            <el-breadcrumb-item>商品分类</el-breadcrumb-item>
        </el-breadcrumb>

        <!-- 卡片区域 -->
        <el-card>
            <!-- 添加分类 -->
            <el-row>
                <el-col>
                    <el-button type="primary" @click="showAddCateDialog">添加分类</el-button>
                </el-col>
            </el-row>

            <!-- 表格占位 -->
            <tree-table class="tree-table" :data="cateList" :columns="columns" :selection-type="false" :expand-type="false" :show-index="true" border>
              <!-- 是否有效 -->
              <template slot="isOk" slot-scope="scope">
                <i class="el-icon-success" v-if="!scope.row.cat_deletede" style="color:lightgreen"></i>
                <i class="el-icon-error" v-else></i>
              </template>

              <!-- 排序 -->
              <template slot-scope="scope" slot="order">
                <el-tag v-if="scope.row.cat_level===0" size="mini">一级</el-tag>
                <el-tag v-else-if="scope.row.cat_level===1" type="success" size="mini">二级</el-tag>
                <el-tag v-else type="info" size="mini">三级</el-tag>
              </template>

              <!-- 操作 -->
              <template slot="opt" slot-scope>
                <el-button type="primary" icon="el-icon-edit" size="mini">删除</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini">编辑</el-button>
              </template>
            </tree-table>

            <!-- 分页区 -->
            <el-pagination
              @size-change="handleSizeChange"
              @current-change="handleCurrentChange"
              :current-page="queryInfo.pagenum"
              :page-sizes="[3, 5, 7, 10]"
              :page-size="queryInfo.pagesize"
              layout="total, sizes, prev, pager, next, jumper"
              :total="total">
            </el-pagination>
        </el-card>

        <!-- 添加分类的对话框 -->
        <el-dialog title="添加分类" :visible.sync="addCateDialogVisible" width="50%" @close="addCateDialogClosed">
        <!-- 添加分类的表单 -->
        <el-form :model="addCateForm" :rules="addCateFormRules" ref="addCateFormRef" label-width="100px">
          <el-form-item label="分类名称：" prop="cat_name">
            <el-input v-model="addCateForm.cat_name"></el-input>
          </el-form-item>
          <el-form-item label="父级分类：">
            <el-cascader :options="parentCateList" :props="cascaderProps" v-model="selectedKeys" @change="parentCateChange"  expandTrigger= 'hover' clearable change-on-select>
            </el-cascader>
          </el-form-item>
        </el-form>
        <span slot="footer" class="dialog-footer">
          <el-button @click="addCateDialogVisible = false">取 消</el-button>
          <el-button type="primary" @click="addCate">确 定</el-button>
        </span>
      </el-dialog>
    </div>
</template>

<script>
export default {
  data() {
    return {
      // 商品分类的数据列表
      cateList: [],

      // 查询商品分类数据的条件
      queryInfo: {
        pagenum: 1,
        type: 3,
        pagesize: 5
      },

      // 总数据条数
      total: 0,

      // 指定列的定义
      columns: [{
        label: '分类名称',
        prop: 'cat_name'
      }, {
        label: '是否有效',
        // 指定当前列为模板列
        type: 'template',
        template: 'isOk'
      }, {
        label: '排序',
        type: 'template',
        template: 'order'
      }, {
        label: '操作',
        type: 'template',
        template: 'opt'
      }],

      // 是否显示添加分类对话框
      addCateDialogVisible: false,

      // 添加分类的表单数据对象
      addCateForm: {
        cat_name: '',
        cat_pid: 0,
        cat_level: 0
      },

      // 添加分类表单的验证规则
      addCateFormRules: {
        cat_name: [
          { required: true, message: '请输入分类名称', trigger: 'blur' }
        ]
      },

      // 父级分类列表
      parentCateList: [],

      // 指定级联属性的配置对象
      cascaderProps: {
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },

      // 选中的父级分类的id数组
      selectedKeys: []
    }
  },
  created() {
    this.getCateList()
  },
  methods: {
    async getCateList() {
      const { data: res } = await this.$http.get('categories', { params: this.queryInfo })
      if (res.meta.status !== 200) return this.$message.error('获取失败')
      this.cateList = res.data.result
      this.total = res.data.total
    },

    // 监听pagesize事件
    handleSizeChange(newSize) {
      this.queryInfo.pagesize = newSize
      this.getCateList()
    },

    // 监听pagenum的改变
    handleCurrentChange(newPage) {
      this.queryInfo.pagenum = newPage
      this.getCateList()
    },

    // 点击显示添加分类的对话框
    showAddCateDialog() {
      this.getParentCateList()
      this.addCateDialogVisible = true
    },

    // 获取父级分类的数据列表
    async getParentCateList() {
      const { data: res } = await this.$http.get('categories', { params: { type: 2 } })
      if (res.meta.status !== 200) return this.$message.error('请求失败')
      this.parentCateList = res.data
    },

    // 父级发生改变时触发
    parentCateChange() {
      // 如果selectedKeys为空则未选中分类，反之已选中分类
      if (this.selectedKeys.length > 0) {
        this.addCateForm.cat_pid = this.selectedKeys[this.selectedKeys.length - 1]
        this.addCateForm.cat_level = this.selectedKeys.length
      } else {
        this.addCateForm.cat_pid = 0
        this.addCateForm.cat_level = 0
      }
    },

    // 添加分类列表
    addCate() {
      this.$refs.addCateFormRef.validate(async valid => {
        if (!valid) return
        const { data: res } = await this.$http.post('categories', this.addCateForm)
        console.log(res.meta)
        if (res.meta.status !== 201) return this.$message.error('添加分类失败')
        this.getCateList()
        this.$message.success('添加分类成功')
        this.addCateDialogVisible = false
      })
    },

    // 关闭添加分类框
    addCateDialogClosed() {
      this.selectedKeys = []
      this.$ref.addCateFormRef.resetFields()
      this.addCateForm.cat_level = 0
      this.addCateForm.cat_pid = 0
    }
  }
}
</script>
<style lang="less" scoped>
  .tree-table {
    margin-top: 15px;
  }

  .el-cascader {
    width: 100%
  }
</style>
